Major human airways diseases, including CORD and CF, exhibit obstruction of airway lumens with mucus. This tPPG is based on the premise that novel biophysical and biochemical hypotheses are required to adequately describe airway mucus transport in health, predict how and when the system fails in disease, and invent novel therapies to treat these ainways diseases. We hypothesize that effective and specific therapies will require dual therapeutic activities: 1) a mucus hydrating activity; and 2) a mucolytic activity, i.e., an agent that wil decrease mucus cohesion and/or adhesion. This tPPG application presents three Projects and five Cores designed to provide the scientific basis, biomarkers, and tests of novel therapies to treat muco-obstructive diseases. The Administrative Core (Core A) will oversee the fusion of physical and biological sciences that underpins our attack on this problem, key pre-clinical models for testing novel therapeutic strategies, and clinical trials to accomplish our overarching goals of: 1) testing in human subjects novel delivery devices and single/combination therapies focused on airway re-hydration; and 2) developing a novel mucolytic platform and testing inhibitors of mucin gene transcription. Thus, Core A will oversee three Projects: 1) The Biophysics of Mucus Hydration and Adhesion/Cohesion -Michael Rubenstein, Ph.D., P.I.; 2) Mucus Obstructed Mice for Biomarker and Drug Development - Richard Boucher, M.D., P.I.; 3) Targeting Defective Mucus Clearance in COPD - Scott Donaldson, M.D., P.I. Core A will oversee four Cores: 1) Core B (the Biostatistics and Data Management Core); 2) Core C (the Mucus Core), which will provide state-of-the-art measurements of mucin concentration/biophysical properties; 3) Core D [the Pharmacokinetics/Pharmacodynamics (PK/PD) Core], which will provide a range of PK/PD methodologies for testing activities of topical muco-active agents; and 4) Core E (the Compound/Combination Selection Core) - which will provide in vitro and animal model screens. In sum, the activities of the tPPG are integrated to provide the scientific bases to initiate clinical studies of novel delivery devices, to test combinations of hydrating agents, and to develop a new mucolytic drug for therapy of COPD.